
Walter Roberson
I do not do free private consulting. If you want to bring my attention to something, send a link to the MATLAB Answers location. I am currently caught up to T0099119; if you are waiting on a reply from me for an older issue, please send me a reminder.
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How do I get normal numerical answers using solve or vpasolve?
Use sym(pi,'d') instead of pi Or... use sympref to set floating point output on Or... Use vpa Or... Use double. For examp...
1 hour 前 | 0
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Good evening. If possible, I would like a comprehensive explanation of cell-free technology in 6G. If there is a MATLAB code available with it, I would be very grateful.
An explanation of cell-free technology is a large topic that is beyond the scope of MATLAB Answers. Providing MATLAB code for a...
2 hours 前 | 1
Can I upload excel input and output data in PSO to define objective
Yes. It is inefficient to do this for inputs; you should instead read the data once before the pso() call and use function para...
2 hours 前 | 0
error: Undefined function 'on' for input arguments of type 'double'. How can i fix this error (i use matlab app designer)?
typefunction = app.TypefunctionEditField.Editable; fxi=str2func(typefunction); typefunction contains something that includes...
2 hours 前 | 0
I have 4 inputs (P,T,V,H) and 1 output (TS). I want to optimize for TS (maximize in this case). Can I use PSO for this purpose
Yes you can. You might find it easiest to use Problem Based optimization.
3 hours 前 | 0
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I code a bisection method on MATLAB app designer, how can I fix this error ?
fxi=str2func(['@(x)'typefunction]); You need a space or comma, like fxi=str2func(['@(x)' typefunction]);
4 hours 前 | 0
Ode45, Events error: SWITCH expression must be a scalar or a character vector
I have seen this before when the person had a third-party version of lower in their MATLAB path. Please show which -all lower ...
4 hours 前 | 0
Generate specific binary combination
N = 4; for K = 0 : 2^N - 1 thiscombo = dec2bin(K,N); stuff end
11 hours 前 | 1
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selected cell in table app designer
https://www.mathworks.com/help/matlab/ref/matlab.ui.control.table-properties.html#mw_1135e93c-c65f-4439-9112-dc80ae0d6d65 Selec...
16 hours 前 | 0
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I don't know how to solve the error it is producing
fun = @(b, t) cost(db, tb, P, E, H, rho, numIters, segments); fun is a function that expects two parameters, and ignores both o...
18 hours 前 | 0
Need to simulate a keypress in a matlab script
https://www.mathworks.com/matlabcentral/fileexchange/28603-inputemu-keyboard-mouse-emulator-v1-0-1 https://www.mathworks.com/m...
18 hours 前 | 0
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Issues with surface plotting using a large table of data
surf(vector_of_length_54, vector_of_length_12, Your_12_by_54_data) Remember that horizontal (rows) corresponds to Y axes, and v...
19 hours 前 | 0
LDPC encoding using MATLAB encoder
I = randi([0 1],43200,1); % INFORMATION BITS H = dvbs2ldpc(2/3); l = comm.LDPCEncoder(H); codeword = l(I);
19 hours 前 | 1
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Why these two path strings are different? (manual string vs. pwd + fullfile)
You will find that on MacOS and Linux (including here on MATLAB Answers) that fullfile uses / separators
22 hours 前 | 0
Direct calculations on tables - elementwise mean of n-tables
cellfun table2array, cat(3) the expansion of the resulting cell, mean() across the third dimension. array2table the results givi...
23 hours 前 | 0
Is there a uicontrol to let user rearrange rows of strings?
No there is no uicontrol for that purpose.
1 day 前 | 0
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Why I can not start the parpool? I just upload the MATLAB and Toolbox, is this question related to the Lenovo system?
<https://www.mathworks.com/matlabcentral/answers/647218-invalid-character-code-sequence-detected-error-using-parfor-on-matlab202...
1 day 前 | 0
sympref FloatingPointOutput adds roundoff error
That does not happen in current releases, so it must have beeen fixed between R2020b and R2023b format short e u = symunit; ...
1 day 前 | 0
Is there a way to capture the user click on a LiDAR plot?
See https://www.mathworks.com/matlabcentral/answers/62653-convert-currentpoint-to-x-and-y-value#answer_74247 CurrentPoint ref...
1 day 前 | 0
can I ask a several question about automatic control ?
syms u(t) y(t) sigma omega_n dy = diff(y,t) d2y = diff(dy, t); eqn = d2y + 2*sigma * omega_n * dy + omega_n^2 * y == omega_n^...
1 day 前 | 0
I need to plot a graph for this physics problem and I don't know how to do it.
By knowing the cutoff height you can calculate the radius of the circular opening. By knowing the cutoff height you can calcuat...
1 day 前 | 0
is there a way to perform this task w/o using loops?
The more general vectorized strategy would probably be to set up cell arrays of values, and then use the fact that when you stru...
1 day 前 | 0
trouble making a firfilter to remove a tone out of a wavefile
The error is correct, in that the documentation lists specific filter specifications, none of which include Fc https://www.math...
1 day 前 | 0
Changing color of plotting points according to number
Create a small colormap scatter(x, y, [], INDEX) caxis([1, size(YourMap, 1)]) colormap(YourMap)
1 day 前 | 0
Overlay two images using transparency
figure(); FA(FA == 0) = NaN; % I want NAN values to be transparent A = imagesc(flipud(T1w')); % Back...
2 days 前 | 0
Why am I unable to add these elements to an array?
noteLength = durations(randi(durationOption)); A duration is randomly selected note = @(t,freq,oct) sin(linspa...
2 days 前 | 0
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How to display a saved .fig file in uiaxes appdesinger?
You cannot do that. A fig file is a saved figure or saved uifigure. Saved figures and uifigures are windows with attached behavi...
2 days 前 | 1
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why do I receive error like"The input must be a built-in integer or fixed-point data type"
Put in a type conversion block https://www.mathworks.com/help/simulink/slref/datatypeconversion.html
2 days 前 | 0
precision-recall curve for faster rcnn
https://www.mathworks.com/help/vision/ref/evaluateobjectdetection.html was introduced in R2023b, but you have R2023a. There are...
2 days 前 | 0
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problem while getting precision-recall curve
metrics = evaluateDetectionPrecision(detectionResults, testData); The function evaluateDetectionPrecision always returns a ...
2 days 前 | 0